Biosynthesis of -Polyglutamic Acid by Bacillus licheniformis Through Submerged Fermentation (SmF) and Solid-state Fermentation (SSF)

Gamma-Polyglutamic acid (γ-PGA) was produced from fermentation processes by inoculating the bacterium Bacillus licheniformis on different substrates. In submerged fermentation (SmF), glycerol and glucose were used as the main carbon substrates while ammonium sulfate served to provide nitrogen. In so...

Full description

Bibliographic Details
Main Authors: V. Campos, R. M. Kaspary, M. J. Rossi, T. A. D. M. Medeiros
Format: Article
Language:English
Published: Croatian Society of Chemical Engineers 2021-10-01
Series:Chemical and Biochemical Engineering Quarterly
Subjects:
Online Access:http://silverstripe.fkit.hr/cabeq/assets/Uploads/07-3-2021.pdf
Description
Summary:Gamma-Polyglutamic acid (γ-PGA) was produced from fermentation processes by inoculating the bacterium Bacillus licheniformis on different substrates. In submerged fermentation (SmF), glycerol and glucose were used as the main carbon substrates while ammonium sulfate served to provide nitrogen. In solid-state fermentation (SSF), soybean was used as the main substrate. Tests carried out in an airlift bioreactor with B. licheniformis showed a maximum productivity of 0.789 g L–1 h–1 and a yield of 0.4 g g–1. Different soybean cultivars from the 2015 and 2016 crops were used in the SSF. The BRS 1001IPRO cultivar, from the 2016 crop, showed the highest production, i.e., 1.2 g L–1 of γ-PGA. This cultivar was subjected to different levels of milling (fine, intermediate and coarse). Coarsely milled grains increased γ-PGA production to 2.7 g L–1. Moreover, coarse milling made the internal nutrients of the grains available for fermentation and this particle size did not compromise aeration during fermentation.
ISSN:0352-9568
1846-5153